/*
 * Copyright (C) 2007 The Android Open Source Project
 * Copyright (C) 2011 Cedric Fung (wolfplanet@gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.yixia.zi.widget.cropimage;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Region;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.view.View;

import com.yixia.zi.R;

// This class is used by CropImage to display a highlighted cropping rectangle
// overlayed with the image. There are two coordinate spaces in use. One is
// image, another is screen. computeLayout() uses mMatrix to map from image
// space to screen space.
class HighlightView {
	private static final boolean HONEYCOMB_OR_GREATER = (Build.VERSION.SDK_INT >= 11);
	private static final int LAYER_TYPE_SOFTWARE = 1;
	private Method mSetLayerTypeMethod = null;

	public static final int GROW_NONE = (1 << 0);
	public static final int GROW_LEFT_EDGE = (1 << 1);
	public static final int GROW_RIGHT_EDGE = (1 << 2);
	public static final int GROW_TOP_EDGE = (1 << 3);
	public static final int GROW_BOTTOM_EDGE = (1 << 4);
	public static final int MOVE = (1 << 5);

	private View mContext; // The View displaying the image.

	public HighlightView(View ctx) {
		mContext = ctx;
		if (HONEYCOMB_OR_GREATER) {
			disableHWAcceleration(mContext);
		}
	}

	private void init() {
		android.content.res.Resources resources = mContext.getResources();
		mResizeDrawableWidth = resources.getDrawable(R.drawable.cropimage_camera_crop_width);
		mResizeDrawableHeight = resources.getDrawable(R.drawable.cropimage_camera_crop_height);
		mResizeDrawableDiagonal = resources.getDrawable(R.drawable.cropimage_indicator_autocrop);
	}

	boolean mIsFocused;
	boolean mHidden;

	public boolean hasFocus() {
		return mIsFocused;
	}

	public void setFocus(boolean f) {
		mIsFocused = f;
	}

	public void setHidden(boolean hidden) {
		mHidden = hidden;
	}

	protected void draw(Canvas canvas) {
		if (mHidden) {
			return;
		}
		canvas.save();
		Path path = new Path();
		if (!hasFocus()) {
			mOutlinePaint.setColor(0xFF000000);
			canvas.drawRect(mDrawRect, mOutlinePaint);
		} else {
			Rect viewDrawingRect = new Rect();
			mContext.getDrawingRect(viewDrawingRect);
			if (mCircle) {
				float width = mDrawRect.width();
				float height = mDrawRect.height();
				path.addCircle(mDrawRect.left + (width / 2), mDrawRect.top + (height / 2), width / 2, Path.Direction.CW);
				mOutlinePaint.setColor(0xFFEF04D6);
			} else {
				path.addRect(new RectF(mDrawRect), Path.Direction.CW);
				mOutlinePaint.setColor(0xFFFF8A00);
			}
			canvas.clipPath(path, Region.Op.DIFFERENCE);
			canvas.drawRect(viewDrawingRect, hasFocus() ? mFocusPaint : mNoFocusPaint);

			canvas.restore();
			canvas.drawPath(path, mOutlinePaint);

			if (mMode == ModifyMode.Grow) {
				if (mCircle) {
					int width = mResizeDrawableDiagonal.getIntrinsicWidth();
					int height = mResizeDrawableDiagonal.getIntrinsicHeight();

					int d = (int) Math.round(Math.cos(/*45deg*/Math.PI / 4D) * (mDrawRect.width() / 2D));
					int x = mDrawRect.left + (mDrawRect.width() / 2) + d - width / 2;
					int y = mDrawRect.top + (mDrawRect.height() / 2) - d - height / 2;
					mResizeDrawableDiagonal.setBounds(x, y, x + mResizeDrawableDiagonal.getIntrinsicWidth(), y + mResizeDrawableDiagonal.getIntrinsicHeight());
					mResizeDrawableDiagonal.draw(canvas);
				} else {
					int left = mDrawRect.left + 1;
					int right = mDrawRect.right + 1;
					int top = mDrawRect.top + 4;
					int bottom = mDrawRect.bottom + 3;

					int widthWidth = mResizeDrawableWidth.getIntrinsicWidth() / 2;
					int widthHeight = mResizeDrawableWidth.getIntrinsicHeight() / 2;
					int heightHeight = mResizeDrawableHeight.getIntrinsicHeight() / 2;
					int heightWidth = mResizeDrawableHeight.getIntrinsicWidth() / 2;

					int xMiddle = mDrawRect.left + ((mDrawRect.right - mDrawRect.left) / 2);
					int yMiddle = mDrawRect.top + ((mDrawRect.bottom - mDrawRect.top) / 2);

					mResizeDrawableWidth.setBounds(left - widthWidth, yMiddle - widthHeight, left + widthWidth, yMiddle + widthHeight);
					mResizeDrawableWidth.draw(canvas);

					mResizeDrawableWidth.setBounds(right - widthWidth, yMiddle - widthHeight, right + widthWidth, yMiddle + widthHeight);
					mResizeDrawableWidth.draw(canvas);

					mResizeDrawableHeight.setBounds(xMiddle - heightWidth, top - heightHeight, xMiddle + heightWidth, top + heightHeight);
					mResizeDrawableHeight.draw(canvas);

					mResizeDrawableHeight.setBounds(xMiddle - heightWidth, bottom - heightHeight, xMiddle + heightWidth, bottom + heightHeight);
					mResizeDrawableHeight.draw(canvas);
				}
			}
		}
	}

	public ModifyMode getMode() {
		return mMode;
	}

	public void setMode(ModifyMode mode) {
		if (mode != mMode) {
			mMode = mode;
			mContext.invalidate();
		}
	}

	// Determines which edges are hit by touching at (x, y).
	public int getHit(float x, float y) {
		Rect r = computeLayout();
		final float hysteresis = 20F;
		int retval = GROW_NONE;

		if (mCircle) {
			float distX = x - r.centerX();
			float distY = y - r.centerY();
			int distanceFromCenter = (int) Math.sqrt(distX * distX + distY * distY);
			int radius = mDrawRect.width() / 2;
			int delta = distanceFromCenter - radius;
			if (Math.abs(delta) <= hysteresis) {
				if (Math.abs(distY) > Math.abs(distX)) {
					if (distY < 0) {
						retval = GROW_TOP_EDGE;
					} else {
						retval = GROW_BOTTOM_EDGE;
					}
				} else {
					if (distX < 0) {
						retval = GROW_LEFT_EDGE;
					} else {
						retval = GROW_RIGHT_EDGE;
					}
				}
			} else if (distanceFromCenter < radius) {
				retval = MOVE;
			} else {
				retval = GROW_NONE;
			}
		} else {
			// verticalCheck makes sure the position is between the top and
			// the bottom edge (with some tolerance). Similar for horizCheck.
			boolean verticalCheck = (y >= r.top - hysteresis) && (y < r.bottom + hysteresis);
			boolean horizCheck = (x >= r.left - hysteresis) && (x < r.right + hysteresis);

			// Check whether the position is near some edge(s).
			if ((Math.abs(r.left - x) < hysteresis) && verticalCheck) {
				retval |= GROW_LEFT_EDGE;
			}
			if ((Math.abs(r.right - x) < hysteresis) && verticalCheck) {
				retval |= GROW_RIGHT_EDGE;
			}
			if ((Math.abs(r.top - y) < hysteresis) && horizCheck) {
				retval |= GROW_TOP_EDGE;
			}
			if ((Math.abs(r.bottom - y) < hysteresis) && horizCheck) {
				retval |= GROW_BOTTOM_EDGE;
			}

			// Not near any edge but inside the rectangle: move.
			if (retval == GROW_NONE && r.contains((int) x, (int) y)) {
				retval = MOVE;
			}
		}
		return retval;
	}

	// Handles motion (dx, dy) in screen space.
	// The "edge" parameter specifies which edges the user is dragging.
	void handleMotion(int edge, float dx, float dy) {
		Rect r = computeLayout();
		if (edge == GROW_NONE) {
			return;
		} else if (edge == MOVE) {
			// Convert to image space before sending to moveBy().
			moveBy(dx * (mCropRect.width() / r.width()), dy * (mCropRect.height() / r.height()));
		} else {
			if (((GROW_LEFT_EDGE | GROW_RIGHT_EDGE) & edge) == 0) {
				dx = 0;
			}

			if (((GROW_TOP_EDGE | GROW_BOTTOM_EDGE) & edge) == 0) {
				dy = 0;
			}

			// Convert to image space before sending to growBy().
			float xDelta = dx * (mCropRect.width() / r.width());
			float yDelta = dy * (mCropRect.height() / r.height());
			growBy((((edge & GROW_LEFT_EDGE) != 0) ? -1 : 1) * xDelta, (((edge & GROW_TOP_EDGE) != 0) ? -1 : 1) * yDelta);
		}
	}

	// Grows the cropping rectange by (dx, dy) in image space.
	void moveBy(float dx, float dy) {
		Rect invalRect = new Rect(mDrawRect);

		mCropRect.offset(dx, dy);

		// Put the cropping rectangle inside image rectangle.
		mCropRect.offset(Math.max(0, mImageRect.left - mCropRect.left), Math.max(0, mImageRect.top - mCropRect.top));

		mCropRect.offset(Math.min(0, mImageRect.right - mCropRect.right), Math.min(0, mImageRect.bottom - mCropRect.bottom));

		mDrawRect = computeLayout();
		invalRect.union(mDrawRect);
		invalRect.inset(-10, -10);
		mContext.invalidate(invalRect);
	}

	// Grows the cropping rectange by (dx, dy) in image space.
	void growBy(float dx, float dy) {
		if (mMaintainAspectRatio) {
			if (dx != 0) {
				dy = dx / mInitialAspectRatio;
			} else if (dy != 0) {
				dx = dy * mInitialAspectRatio;
			}
		}

		// Don't let the cropping rectangle grow too fast.
		// Grow at most half of the difference between the image rectangle and
		// the cropping rectangle.
		RectF r = new RectF(mCropRect);
		if (dx > 0F && r.width() + 2 * dx > mImageRect.width()) {
			float adjustment = (mImageRect.width() - r.width()) / 2F;
			dx = adjustment;
			if (mMaintainAspectRatio) {
				dy = dx / mInitialAspectRatio;
			}
		}
		if (dy > 0F && r.height() + 2 * dy > mImageRect.height()) {
			float adjustment = (mImageRect.height() - r.height()) / 2F;
			dy = adjustment;
			if (mMaintainAspectRatio) {
				dx = dy * mInitialAspectRatio;
			}
		}

		r.inset(-dx, -dy);

		// Don't let the cropping rectangle shrink too fast.
		final float widthCap = 25F;
		if (r.width() < widthCap) {
			r.inset(-(widthCap - r.width()) / 2F, 0F);
		}
		float heightCap = mMaintainAspectRatio ? (widthCap / mInitialAspectRatio) : widthCap;
		if (r.height() < heightCap) {
			r.inset(0F, -(heightCap - r.height()) / 2F);
		}

		// Put the cropping rectangle inside the image rectangle.
		if (r.left < mImageRect.left) {
			r.offset(mImageRect.left - r.left, 0F);
		} else if (r.right > mImageRect.right) {
			r.offset(-(r.right - mImageRect.right), 0);
		}
		if (r.top < mImageRect.top) {
			r.offset(0F, mImageRect.top - r.top);
		} else if (r.bottom > mImageRect.bottom) {
			r.offset(0F, -(r.bottom - mImageRect.bottom));
		}

		mCropRect.set(r);
		mDrawRect = computeLayout();
		mContext.invalidate();
	}

	// Returns the cropping rectangle in image space.
	public Rect getCropRect() {
		return new Rect((int) mCropRect.left, (int) mCropRect.top, (int) mCropRect.right, (int) mCropRect.bottom);
	}

	// Maps the cropping rectangle from image space to screen space.
	private Rect computeLayout() {
		RectF r = new RectF(mCropRect.left, mCropRect.top, mCropRect.right, mCropRect.bottom);
		mMatrix.mapRect(r);
		return new Rect(Math.round(r.left), Math.round(r.top), Math.round(r.right), Math.round(r.bottom));
	}

	public void invalidate() {
		mDrawRect = computeLayout();
	}

	public void setup(Matrix m, Rect imageRect, RectF cropRect, boolean circle, boolean maintainAspectRatio) {
		if (circle) {
			maintainAspectRatio = true;
		}
		mMatrix = new Matrix(m);

		mCropRect = cropRect;
		mImageRect = new RectF(imageRect);
		mMaintainAspectRatio = maintainAspectRatio;
		mCircle = circle;

		mInitialAspectRatio = mCropRect.width() / mCropRect.height();
		mDrawRect = computeLayout();

		mFocusPaint.setARGB(125, 50, 50, 50);
		mNoFocusPaint.setARGB(125, 50, 50, 50);
		mOutlinePaint.setStrokeWidth(3F);
		mOutlinePaint.setStyle(Paint.Style.STROKE);
		mOutlinePaint.setAntiAlias(true);

		mMode = ModifyMode.None;
		init();
	}

	private void disableHWAcceleration(View view) {
		if (mSetLayerTypeMethod == null) {
			try {
				Class<? extends View> c = view.getClass();
				mSetLayerTypeMethod = c.getMethod("setLayerType", int.class, Paint.class);
			} catch (SecurityException e) {
			} catch (NoSuchMethodException e) {
			}
		}
		if (mSetLayerTypeMethod == null) {
			return;
		}
		try {
			mSetLayerTypeMethod.invoke(view, LAYER_TYPE_SOFTWARE, null);
		} catch (IllegalArgumentException e) {
		} catch (IllegalAccessException e) {
		} catch (InvocationTargetException e) {
		}
	}

	enum ModifyMode {
		None, Move, Grow
	}

	private ModifyMode mMode = ModifyMode.None;

	Rect mDrawRect; // in screen space
	private RectF mImageRect; // in image space
	RectF mCropRect; // in image space
	Matrix mMatrix;

	private boolean mMaintainAspectRatio = false;
	private float mInitialAspectRatio;
	private boolean mCircle = false;

	private Drawable mResizeDrawableWidth;
	private Drawable mResizeDrawableHeight;
	private Drawable mResizeDrawableDiagonal;

	private final Paint mFocusPaint = new Paint();
	private final Paint mNoFocusPaint = new Paint();
	private final Paint mOutlinePaint = new Paint();
}
